The Jersey JournalFederal Transit Administrator Peter Rogoff speaks during the groundbreaking ceremony for the Mass Transit Tunnel project in North Bergen, Monday, June 8, 2009.

TRENTON — Declaring he would not move forward on a project he could not afford, Gov. Chris Christie said today he was the one who put the brakes on the $8.7 billion trans-Hudson rail tunnel.

The governor, in a press briefing, said he liked the idea of the tunnel, but not if he can’t pay for it.

"And if I can’t pay for it, then we’ll have to consider other options," he said, making it clear for the first time the project was in serious jeopardy.

At the same time the governor questioned the cost assumptions of the massive venture — which he said were influenced by the politics of the last gubernatorial election.

"It went from $5 billion to $8.7 billion in what was clearly a rush by the Corzine administration to have gold shovels and put them the ground and try to get (former Gov. Jon) Corzine re-elected. That obviously was less than successful," Christie said. "And I’m concerned that their evaluations of price of this project was as successful as his re-election campaign was."

Assemblyman John Wisniewski (D-Middlesex), who chairs the transportation committee, said the tunnel was in the planning long before Corzine became governor.

"This project has had a variety of estimates, both higher and lower, and they were all dependent on where the tunnel went and a variety of other factors that are considered when you estimate these things," Wisniewski said.

Josh Zeitz, a spokesman for Corzine, said the former governor had been a strong supporter of mass transit and infrastructure investments.

"What he understands, and what Gov. Christie seems not to understand, is that our state will lose jobs and forfeit opportunities for economic growth unless we upgrade our rail and transit facilities," Zeitz said. "This looks like another example of a Trenton politician doing what’s penny wise in the moment, but pound foolish in the long run."

The project, officially known as the Access to the Region’s Core, Trans-Hudson Express Tunnel, is scheduled to be completed by late 2018. It will more than double rail capacity between New Jersey and New York — from 23 trains per hour during peak periods to 48 trains per hour — eliminating a bottleneck that limits any expansion of rail service to New York.

Under the plan, trains will be routed along new tracks from Secaucus Junction and through two new tunnels that will be bored deep below the Hudson, terminating at a new rail station in Manhattan that will be built 100 feet below 34th Street, between 6th and 8th avenues.

The federal government and the Port Authority of New York and New Jersey are each putting in $3 billion for the project; New Jersey’s share is $2.7 billion.

But in recent months, the Federal Transit Administration has been challenging the cost projections, and pushing New Jersey to show how it will cover any budget shortfall. At issue is the state’s Transportation Trust Fund, which helps fund rail projects, is nearly bankrupt.

On Saturday, NJ Transit Executive Director James Weinstein issued a 30-day stop-work order, temporarily shutting down all new construction, and suspending additional bidding on the project.

Work already under way, including a track underpass in North Bergen and a tunnel segment under the Palisades, will continue.

Christie said he had also pulled a resolution for a board vote before the Port Authority on a $500 million contract to advance the project.

"Let’s figure out how much this thing’s going to cost and how we’re going to pay for it. I just think that’s a common sense way to approach things," he said. "We’re in a 30-day mode to have somebody give me a realistic idea of how much money is at stake here."

New Jersey’s Democratic U.S. senators, Robert Menendez and Frank Lautenberg, both have warned the suspension could threaten $3 billion in federal grant funding they worked on obtaining for the state.

"We’ve done everything we can to keep it on track," Menendez said. "But the people who are running it is NJ Transit and the bottom line is that we have they have get this done. We can’t dig the tunnel ourselves."

Christie, however, said he will not move forward on a project that leaves the state responsible for billions in potential cost overruns.

"I’m not going to tell the people of the state of New Jersey, ‘Hey, trust us. We’ll get it right. We’ll figure out how to pay for it later.’ They’ve been down that road before. It’s been a losing road for them."